Sailboat



J. H. SHELLEY Jan. 3, 1967 SAILBOAT 3 Sheets-Sheet 1 Filed Aug. 20, 1965 INVENTOR John Henry SheNey ATTORNEYS Jan. 3, 1967 J. H. SHELLEY 3,295,152

SAILBOAT Filed Aug. 20, 1965 5 Sheets-$heet 2 N 5 w I INVENTOR John Henry Shelley BY M ,4 M

ATTOR NE Y5 J. H. SHELLEY Jan. 3, 1967 SAILBOAT 3 Sheets-Sheet 3 Filed Aug. 20, 1965 INVENTOR John Henry Shelley ATTO RNEYS United States Patent 01 3,295,152 SAILBOAT John H. Shelley, Chez Nous, Msida, Malta Filed Aug. 20, 1965, Ser. No. 481,258 9 Claims. (Cl. 96)

This invention relates to sailboats and improvements therein and more particularly to improvements in the structure and conformation of the hulls of such sailboats.

In the sport of sailing, boats are grouped into classes defined by such characteristics as rigging and length. One such class is designated as the International Moth class of sailboat and is particularly characterized by the relatively short length of the sailboats so classified.

A short length from bow to stern has proven by past experience to be a difiicult requirement from the standpoint of speed and stability, since a short length must have have associated therewith a relatively wide beam for accommodation of a sailor and for the sake of stability. Thus, a constant and perplexing problem is present in the art to achieve a more efii'cient hull design without exceeding the length requirement of any given class of boats and in particular, a class requiring a relatively short length of the hull.

It is, therefore, an object of this invention to provide a new and novel hull for boats which increases the efiiciency and speed thereof for a given hull length.

Another object of this invention is to provide a new and novel conformation and structure for boat hulls.

Still another object of this invention is to provide a new and novel hull conformation for boats having as a primary characteristic the property of locating the greatest beam width thereof aft of amidships.

Still another object of this invention is to provide a new and novel hull conformation for boats in which the sides of the hull transcend from a convex curvature at the bow thereof to a concave curvature at the stern.

Still another object of this invention is to provide a new and novel hull conformation for boats in which the sides of the hull transcend from a convex curvature at the bow thereof to a concave curvature at the stern; and wherein the said hull is completely formed from two pieces of plywood or like sheet material, each preformed in a new and novel configuration.

Yet another object of this invention is to provide a new and novel hull for boats in which the number of lateral reinforcing rib structures are minimized.

These and other objects of this invention will become more readily apparent with reference to the following specification and drawings which relate to a preferred embodiment of the present invention.

In the drawings:

FIGURE 1 is a top plan view of the hull of the present invention;

FIGURE 2 is a bottom plan view of the hull of the present invention;

FIGURE 3 is a front end view of the hull of the present invention;

FIGURE 4 is a detailed cross-section taken along line 44 of FIGURE 1;

FIGURES 5A, 5B and 5C are cross-sections taken respectively along lines AA, BB and CC of FIG- URE 3;

Patented Jan. 3, 1967 ice FIGURE 6 is a plan view of the transom of the hull of the present invention; and

FIGURE 7 is a rear end view of the hull of the present invention.

Referring in detail to the drawings and more particularly to FIGURES 1, 2 and 3, the hull 19 of the sailboat of the present invention is shown as comprising a cockpit portion 12, an upper deck portion 14 and a shell portion 16.

The shell portion 16 is formed of two symmetrical pieces of sheet material, 18 and 20, respectively, of marine plywood or the like, having a common joint 22 along the centerline of the shell 16.

The first and second shell elements 18 and are formed, respectively, by utilizing first and second curvilinear saw cuts 24 and 2-6 extending from the transom or stern 28 of the hull 11) approximately two-thirds /3 of the distance to the bow 30 of the hull 10; then subsequently deforming the said shell elements 18 and 20 to effect a variable radius curvature of the shell in lateral cross-section along the bottom 32. of the shell 16; and further deforming the side portions 34 of the shell 16 from the chine cuts 24 and 26 to the decking 14 such that from bow to stern a smooth transition is effected from a convex curvature at the bow 30, through a substantially straight line profile aft of amidships to a concave curvature at the transom 28. In addition, the shell sections 18 and 20 and the respective chine cuts 24 and 26 are so shaped and so proportioned as to constrain the maximum beam width of the hull 10 to occur aft of amidships, such as for example, approximately two-thirds of the distance from bow 30 to the transom 28.

The bow 30 is provided with a truncated conformation effected by a capping block 35 which is generally triangular in front end view and semi-circular in cross-section, making same a conic section type of shape extending from an apex 36 at the center joint 16 to its maximum cross-section 38 adjacent the decking 14.

Referring additionally to FIGURES 5A, 5B, 5C, 6 and 7, the upper decking 14 is shown as comprising first and second plywood deck sheets 40 and 42, respectively. From the bow 30 to the line AA in FIGURE 4, as shown in the cross-section of FIGURE 5A, the deck sheets 40 and 42 are formed in a convex curvature meeting at a central longitudinal ridge or chine 44, the latter extending from the bow 30 to the front molding 46 of the cockpit 12.

Since the decking 14 supports the mast 48 in a footing 50, the latter being on the decking chine 44 adjacent the front molding 46 of the cockpit 12, the decking sheets 40 and 42 are reinforced by contoured lateral deck beams 52 and 54 fore and aft of the mast footing 50, a longitudinal stringer 56 connecting the deck beams 52 and 54 along the deck chine 44, and a metal reinforcing tube '58 or the like extending from a strongback structure 60 in the hull 10 to the bottom of the said mast footing 50, whereby the said footing and the mast 48 are fully supported in compression.

From the vicinity of the line AA of FIGURE 4, the decking sheets 40 and 42 undergo a smooth transitional change in cross-sectional curvature to that of a straight line by the time the line B-B of FIGURE 4 is reached as illustrated in FIGURE 5B, and remain in this con- 3 figuration all the way to the transom 28 as illustrated in FIGURES C and 6.

The decking sheets 40 and 42 and the hull sheets 18 and 20 are joined together along a pair of external gunwale strips 62 and 64 to complete the hull 10.

Referring now to FIGURES 1, 4 and SE, a centerboard case 66 is provided in which a vertically disposed removable keel or centerboard slot 63 is defined opening through the hull with the upper end of the said slot 68 being well above the water line of the hull 10. A centerboard or keel member 70 is shown in FIGURE 4 in place in the keel slot 68.

The centerboard case 66 is anchored and reinforced forward by a first integral king post 72 juxtaposed with the strongback structure 60; and is anchored and reinforced aft by a second integral king post 73 having a heavy transverse cross-rib 74 juxtaposed therewith and rigidly affixed thereto by means of horizontal gussets 76 on either side of the centerboard case and vertical gussets 78 on either side of a longitudinal aft strongback rib 80 extending from the said second king post 73 along the centerline joint 22 of the shell 16 to the transom 28.

The hull assembly 10 is strengthened between the decking 14 and the shell 16 by means of space conforming first, second and third gussets 82, 84 and 86, located aft of the centerboard case 66 on both sides of the hull 10.

An alternate means of reinforcement for imparting optimum strength and weight characteristics to the hull 10 is best illustrated in FIGURES 1, 5B and 5C as follows:

The floor or bottom portion 32 of the shell 16, in the cockpit 12, is provided with ,longitudinal stringers 88 of spruce or the like which extend the length of the cockpit 12 in parallel relationship with the aft strongback rib 80. These stringers 88 are utilized when a given plywood thickness such as 7 inch is used for the shell sheets 18 and 20.

Alternatively, the stringers 88 may be eliminated and contoured first and second reinforcing panels 90 and 92 are laminated respectively, to the first and second shell sheets 18 and 20 inside the shell 16 and within the defining boundary of the chine cuts 24 and 26, respectively; the said reinforcing panels having a substantially similar outer contour to that of the said chine cuts and being substantially parallel to the aft strongback 80 and extending from just forward of the second king post 73 to a position forward of the transom 28. This form of reinforcement is particularly desirable when a thinner plywood, for example A3 inch thick, is utilized for the shell sheets 18 and 20. Then a like thickness is preferably utilized for the reinforcing sheets 90 and 92. The said reinforcing sheets and the said shell sheets are laminated by known techniques utilizing strong cementitious materials such as the Well-known epoxy resin base cements.

Should similar thin plywood be used for the first and second deck sheets 40 and 42, first and second deck reinforcing panels 94 and 96, coextensive with the longitudinal dimensions of the shell reinforcing panels 90 and 92, respectively, are laminated to the underside of the deck sheets 40 and 42 respectively. Thus, the area of the deck most often bearing the weight of a sailor is adequately stifiened and strengthened to prevent fatique failure or the like.

Further reinforcement is provided for the hull 10 as follows:

Fiberglass tape 98 is cemented over the deck chine 44 by known techniques utilizing epoxy resins and the like.

Additional fiberglass tapes 100 and 102 are coterminously disposed, respectively, along the chine cuts 24 and 26 and cemented in place by the same known techniques utilizing synthetic resins. The tapes 100 and 102 may, for example, each include a tape within the hull as well as a tape on the outer surface of the hull engaging both the sides 34 and the bottom 32 on either side of their respectively associated chine cuts. In this way, maximum strength with very little increase in weight is achieved.

Because of the presence of the fore and aft strongback assemblies 60 and 80, the center joint 22 of the shell 16 need not be glass taped but need only be caulked. However, if it is so desired, glass tape may be secured in place over the joint 22 in the same manner as that used to cover the chine cuts 24 and 26.

The sides 34 of the shell 16 are internally reinforced by conforming coterminous longitudinal stringers 104 located approximately half the distance between the chine cuts 24-26 and the respective gunwales 62-64.

Since the mast 48 is adapted to be held in place by tension members in the form of three or more shroud lines, anchor blocks 106 and 108 are provided beneath the deck members 40 and 42 adjacent the gunwales 62 and 64, respectively, and are joined together by a hollow metal tube 110 extending transversely of the deck 14, whereby the compression load on the hull 10 caused by the lateral shroud lines (not shown) is fully supported by the said transverse tube 110.

The hull assembly 10 is completed by providing a suitable tiller assembly 112 mounted on the transom 28.

As can be readily seen from the foregoing specification and drawings, .this invention provides a new and novel hull assembly for sailboats and the like characterized by optimum strength, minimized weight, and efliciency of design within prescribed limits of bow-to-stern length.

The location of maximum beam width aft of amidships; the bow-to-stern transitional variation from short to long radius of curvature of the bottom of the shell portion of the hull; the bow-to-stern transition of the sides of the shell from convex curvature, through straight line curvature in the immediate vicinity of the maximum beam width to a concave curvature at the transom; and the various reinforcing and other structural features previously described herein result in a stronger, more stable and faster sailing hull design than has heretofore been provided.

It is to be understood that the embodiment shown and described herein is exemplary and is not intended to limit the scope of the appended claims.

What is claimed is:

1. In a boat hull, the invention comprising a shell constructed of two like adjacent pieces of flexible sheet material convergently formed at one end to form a bow portion and divergently formed at the other end to form a stern portion, first means effecting a maximum beam width of said shell aft of amidships and forward of said stern portion, said shell having a bottom portion, and second means effecting a continuous transition of said bottom portion from a relatively short radius convex curvature at said bow to a relatively large radius convex curvature at said stem.

2. In a boat hull, the invention comprising a shell constructed of two like adjacent pieces of flexible sheet material convergently formed at one end to form a bow portion and divergently formed at the other end to form a stern portion, a common joint between said pieces comprising the centerline of said shell, said shell including sides and a bottom, and means providing a predetermined configuration to said shell wherein said sides of said shell elfect a continuous transition from convex curvature at said bow, through a straight line curvature aft of amidships, to a concave curvature at said stern.

3. The invention defined in claim 2, wherein said shell further includes means effecting a maximum beam length of said shell aft of amidships.

4. The invention defined in claim 2, wherein said means providing said predetermined configuration comprises first and second chine cuts in each of said pieces of sheet material extending in a predetermined curvature from within said convex curvature area of said sides to the said stern, flexible tape means laminated with said piece qo ermiuqus with and fully closing said chine cutsand transom means interconnecting said pieces at said stern. t

5. The invention defined in claim 2, wherein in said predetermined configuration, the said bottom of said shell effects a continuous transition from a short radius convex curvature at said bow to a large radius convex curvature at said stern.

6. The invention defined in claim 5, wherein said shell further includes means efiecting a maximum beam length of said shell aft of amidships.

7. The invention defined in claim 5, wherein said means providing said predetermined configuration comprises first and second chine cuts in each of said pieces of sheet material extending in a predetermined curvature from within said convex curvature area of said sides to the said stern, flexible tape means laminated with said pieces coterminous with and fully closing said chine cuts and transom means interconnecting said pieces at said stern.

8. The invention defined in claim 5, wherei the said bow is of truncated cross-section at the foremost portion UNITED STATES PATENTS 2,122,300 6/1938 Smith et al. 9-6 X 2,520,782 8/1950 Raveau 9-6 2,721,341 10/1955 Roberts et al 96 MILTON BUCHLER, Primary Examiner.

B. BELKIN, Assistant Examiner. 

1. IN A BOAT HULL, THE INVENTION COMPRISING A SHELL CONSTRUCTED OF TWO LIKE ADJACENT PIECES OF FLEXIBLE SHEET MATERIAL CONVERGENTLY FORMED AT ONE END TO FORM A BOW PORTION AND DIVERGENTLY FORMED AT THE OTHER END TO FORM A STERN PORTION, FIRST MEANS EFFECTING A MAXIMUM BEAM WIDTH OF SAID SHELL AFT OF AMIDSHIPS AND FORWARD OF SAID STERN PORTION, SAID SHELL HAVING A BOTTOM PORTION, AND SECOND MEANS EFFECTING A CONTINUOUS TRANSISTION OF SAID BOTTOM PORTION FROM A RELATIVELY SHORT RADIUS CONVEX CURVATURE AT SAID BOW TO A RELATIVELY LARGE RADIUS CONVEX CURVATURE AT SAID STERN. 